1. Field of the Invention
This invention relates to a radio apparatus which provides services to other devices through radio communications, and a link loss recovery method in radio communications with other devices.
2. Description of the Related Art
A cellular phone (radio apparatus) which can perform short-range radio communications using a Bluetooth technique operates as a server, and can provide various services to other devices (devices such as car equipments and personal computers) with a radio communication unit. For example, a cellular phone can provide a handsfree service. The user using the device provided with the handsfree service from the cellular phone can talk with the other party connected via a communication network by the cellular phone, by using a microphone or a speaker for telephone conversation provided on the device.
Such a cellular phone performs reconnection with the device when a communication link with the device is disconnected (link loss). For example, “MCPC TR-00x Ver.1.0 HANDSFREE PROFILE Technical Reference” Ver.1.0, Dec. 25, 2003, p. 15 discloses, as a recommended matter for service level connection, that the car equipment performs reconnection of the service level connection when a link loss occurs in the service level connection between the cellular phone and the car equipment.
Usually, to recover the link loss, it is necessary to render one of the cellular phone and the device a state of waiting a connection request (server state). When the device in the server state receives a connection request from another device, it establishes a communication link with the other device. Therefore, if the cellular phone becomes a connection request waiting state (server state) after a link loss, the cellular phone may receive a connection request from another device different from the device connected with the cellular phone before link loss. In such a case, if the cellular phone establishes a communication link with another device in response to a connection request, it is impossible to continue to provide the service to the device connected before the link loss.